Full Body Momentum (also called foot energy) is achieved when one uses their foot energy to boost their telekinesis. It is often overlooked, as elves tend to use their hands more. Alvar taught it to Keefe in Book 5: Lodestar, and Keefe taught it to Sophie in Book 7: Flashback.
Using this skill, Sophie managed to not just smash one vial, but bring all the vials in Elwin's Office off of the shelves, crashing to the ground. However, she saved them all before they could hit the ground using telekinesis.